Portable crank journal grinder



Aug. 17, 1948. w. F. EMORY 2,447,117

PORTABLE CRANK JOURNAL GRINDER Filed Feb. 12, 1946 3 Sheets-Sheet lFig.5.,

M/fiL TEE F fMo/e Y.

Aug, 17, 1948. w. F. EMORY PQRTABLE CRANK JOURNAL GRINDER 5 Sheets-Sheet2 Filed Feb. 12, 1946 2 H441 TEE F 517012 4 I gdfumrg Aug. 17, 1948.. w.F. EMORY 2,447,117

PORTABLE CRANK JOURNAL GRINDER Filed Feb; 12, 1946 3 Sheets-Sheet 3Patented Aug. 17, 1948 UNITED STATES PATENT OFFICE 2,447,117: PGRTABLECRANK JOURNAL GRINDER Walter F. Emory, Arbutus, Md. Application February12, 1946, Serial No. 647,029

5 Claims.

This invention relates to the preparation of machinery for accuratealignment, and more particularly to the grinding of crank shafts toalign with the bore of the cylinders and main bearings without removingthe crank shaft from its main bearings.

The grin-ding of a crank shaft to make it round accurately isconventionally accomplished by the use of a grinding machine especiallybuilt for receiving the crank shaft and revolving it so the specificbearing tobe ground will be rotated on its axis, an abrasive wheel isrotated against the surface of the bearing until the grinding iscompleted. Using the conventional method explained herein the crankshaft must be removed from its engine bearings. placed in the grinder tosuit the throw of the bearing to be ground, then removed and replacedin-the engine or other device from which it wasremoved. Grinding aneccentricby this method aligns the various bearings of the crank shaftwith each other but does not align the bearings with the bore of thecylinders.

In a particular form of this invention, the grinding of crank shafts tobe repaired, especially those of a peculiar type, such as thoseemanating eccentrically from a bearing, is pursued by employing a motoroperated grinding Wheel of suitable texture actuated through an extendedquill shaft and held to the shaftbearing to be 1 ground at one end andpivotably attached to a pistonwhich reciprocates in the cylinder attheother. The arrangement rotates the crank shaft and the quill shaftinduces the abrasive wheel to grindthe peripheralsurface-of theeccentric shaft on an axis at right angles to that of the shaft to berepaired. At the same tim any grindings ordust involved are evacuated ina very effective and convenient manner.

It is an object of the present invention to provide a new and improvedform of'shaft grinding unit that will avoid one or more of thedisadvantages and limitations of the prior art;

An additional object of the invention is to'provide a new andimprovedshaft grinding unit that may be applied to shafting difficult to get'atbyreason of their structural positions in their equipment', andaccomplish the grinding accurately, conveniently and effectively.

- A further object of this invention is to provide anew and'improvedshaft grinding unit that will be adapted to remove the grindings arisingduring the operation, in an effective and safe manner withoutinterfering or diminishing the operational effectiveness ofthe grinding:functions.

Still another object of the invention is to provide a new and improvedshaft grinding unit, that can be effectively utilized on crank shaftswithout dismantling them, from their parent equipment for the purpose.

In order to illustrate and for other objects reference is made to theappended drawings and following specifications wherein a particular formof sented by way of example, while the claims are particularly worded toset out the invention.

Referring to the drawings:

Figure l is a side elevation of the crank shaft grinder embodying thisinvention,

Figure 2 is a front view of Figure 1,

Figure 3 is an enlarged View showing the longi-- tudinal abrasive wheelfeed and vacuum lines,

with parts broken away to show its construction; Figure 4 is a sectionalView taken along line' l--4 of Figure 3,

Figure 5 is a sectional view taken along line 5-5 of Figure 4.

Figure 6 is an enlarged front view of the crank grinding end,

Figure '7 isan enlarged side View of Figure 6,

Fi ure 8 is a sectional View taken along line 8B'of Figure '7, and

Figure 9 is a sectional view taken along line 9-9 of Fig. 1.

Similar reference characters refer to similar parts throughout thedrawings.

In the particular form indicated in the drawings, a portable grindingunit is shown processing the bearing surfaces of an engine shaft to'bring them down to an accurate roundness or circularity. The bearingvsurfaces indicated are those derived at the crank portion andconnection.

The engine shaft is designated as ID, with its crank structure I l andits crank bearing shaft as l2. The bearing shaft !2 is the one to beground to size and roundness by the invention, and is revol'ved'by theengine or some motor without removal from its main bearings or generalplacement' in the engine.

The. grinding unit comprises a shaft engaging shieldthatlocks over thecrank bearing l2 to be ground. The shield is made in split halvessuitably bolted together, so it may be slipped over the shaft while inplace on the engine. The halves are'provided'with wedges or plungers 14that adjustably contact with the peripheral surface of the shaft andalign the unit properly in regard to it for grinding. Felt pieces I3 areused for win-- ing' grindings from the shaft and for lubricating thebracket plates 55. The upper half l5 of the the invention explicitly theinvention is pre-' 3 shield adjusts in the vertical direction to andfrom the shaft. The adjustment is made by hand and operated by the wheelor handle l8. The shield is preferably provided with transparentmoveable windows 24. The shield is welded to a tubular quill casing IQof relatively large diameter. A quill shaft is secured to the grindingwheel l6 and rotates when turned by a motor 2| distantly connected toit. The quill shaft 20 is journalled in the feed mechanism using a ballbearing element 22. Conventional means are used to hold the Wheel inplace. The abrasive wheel I6 is preferably flat and disc-like and setstangentially to the shaft l2 that it is to grind. The quill shaft 20runs within a close fitting quill housing 23 which is of tubular crosssection and rests on the mechanism I1 and tensioned by spring 68. Spacedaround the quill housing 23 is a tubular quill casing l9 that isattached to the upper half i5 of the shield at its lower end and to thesaddle 25 at the upper flange 26. The spacin 28 between the quillhousing and the quill casing is sufiicient to provide a duct of amplearea to permit an evacuating fiow through it under the action of avacuum pump 21. The saddle is held on coiled springs 29 and bolts 30 andaffords a resilient support for the unit. The spring 3| positionedbetween the duct closing washers 32 and the supporting saddle 25 acts asan absorber and frictional resistance to the movement of the Washers asthe lateral adjusting mechanism 34 reciprocates the quill shaft andquill housing within the casing. The mechanism 34 actuates manually andis operated by gearing 35 and the shaft 36. Limit stops 48 adjusted byscrew threaded arrangement serve to control the travel of the adjustmentof the mechanism 34. A suspension structure 31 supports the motor 2|from the bell and flange 38 mounted on the upper end of the quillhousing. The bell is interiorly large enough to include a series ofspring washers 39 and ball bearings 40 to take up the vertical expansionand thrust, and acts as a buffer under a coupling 4| that connects theshaft 42 of the motor 2| to the quill shaft 20. The motor is suppliedwith electrical service through wiring 62 in any suitable manner. Thespacing 28 is evacuated through the side ducts 43 which are depressed at33 to allow the motor to move from side to side as the quill housing ismoved in the quill casing to feed the abrasive wheel across the bearingto be ground. The side ducts 43 are connected to flexible piping 44 thatruns to the vacuum pump 21 and tank. The weight of the unit duringoperation is minimized by a counter weight 45 attached to the cables 46running over pulley 41 supported from above the unit. In order to takeup the eccentric motion of the crank shaft as the crank is rotated onits axis, a special piston 50 is used in the cylinder of the engine, inplace of the original one and its connecting rod. The piston 50 isprovided with a trunnion which acts as a cross-head so that the grindingmechanism can oscillate therein like a connecting rod and cause thecrank bearing to be ground in proper alignment with the bore of thecylinder. The piston 50 and trunnion 5| are connected with the quillcasing l9. The unit is intended to grind crank bearings while the crankshaft of an engine 10 or the like is still in position and withoutdisassembling or dismantling same from it, only the original piston andconnecting rod has to be displaced during the grinding by the grinderunit. During the process of grinding on the crank bearing the piston 50with its trunnion and housing parts and motor reciprocate in thecylinder of the engine in place of its piston and connecting rod, andsimulates its action with regard to the crank shaft and crank bearing.This assures a grinding that follows actual operating conditionsaccurately, and produces a bearing that is axially correct. A pair ofbracket plates preferably comprise the side walls of the shield Darts I5and i6 and are used to enclose the ends and to provide bearing surfacesthat ride on the fillets of the crank bearing I2 to be ground during thefirst part of the operation. The lower portion of the bracket plates 55are provided with slots 56 to allow the edge of the abrasive wheel It toproject through the slot and grind a fillet at each side where thereground surface of the crank bearing 2 meets a crank structure ll ofthe engine shaft Ill. The bracket plates 55 are tied together by spacers54. One of the upper spacers 54 is used to support a removable diamond52 held by a spring member 53 and serves to keep the grinding wheel I 6in shape for its use, and is used whenever the wheel is to be dressed.

The operation of the device is relatively imple. The piston andconnecting rod is removed from the engine. The shield is attached to thecrank bearing to be ground, the bracket plates 55 are positioned on thefillets, while the grinding unit is suspended and counterbalanced by theweight. Adjustment is made through the wheel or handle It! to bring thewheel l6 against the crank bearing i 2 to be ground round, The motor 2|is started and through the coupling 4| rotates the quill shaft 20 andgrinding wheel IS. The mechanism 34 is actuated and causes the quillhousing and quill shaft to reciprocate back and forth parallel with theaxis of the crank bearing face in a slow but regular movement during thetime that the grinding continues. The engine shaft I 0 is revolved atabout 6 R. P. M. during the time the .crank bearing is being ground. Asthe dust and grindings accumulate they are drawn up into the spacing 28,thence up through the ducts 43 and 44 by a suction pump and discarded.At suitable intervals the operator moves the feed mechanism I1 slightamounts to grind and keep adequate contact with the periphery of thecrank bearing l2. 'During this work, the Various vibrations and stressesarising in the device are taken up by the various springs mentioned. Thecounterweight creates a balance which takes up the weight of thegrinding unit and so improves the operation of the grinding wheel thatit can grind with very close tolerances. In practice this has been foundto be up to .00025 of an inch, whereas using the same machine withoutthe counterbalance the tolerance was .005 of an inch. When the crankbearing has been ground, the wheel I6 is raised and the removablediamond 52 through its spring member 53 is attached to the spacer 54.The revolving wheel I6 is rotated back and forth across the diamonduntil its face is trued, the diamond is then removed. The rollerbearings 51 and the wedges or plungers |4 operate under tension and maybe tightened to take up the bearing of the grinding unit so the grindingwheel may be projected beyond the edges of the bracket plates and grindthe fillets in alignment with the face of the crank bearings. The shieldis then parted and the grinding unit removed from the engine cylinderand moved to the next operation.

While but one general form of the invention is shown in the drawings anddescribed in the specifications it is not desired to limit thisapplication to this particular form or in any other way otherwise thanlimited by the scope thereof, as it is appreciated that other formscould be made that would use the same principles and come Within thescope of the appended claims.

Having thus described the invention what is claimed is:

l. A grinding unit for cylindrical surfaces comprising, a shield adaptedto encompass said surfaces, means for adjustably attaching the shield tosaid surfaces, a quill casing connected with the shield and extendingtherefrom in a predetermined directional manner, a saddle mounted on thecasing, a quill housing within the quill casing and spaced therefrom toprovide an evacuating duct therebetween, a quill shaft longitudinallydisposed within said housing and having its operating head locatedadjacent the surfaces and adapted to hold a grinding wheel forprocessing same, mechanism mounted on the casing and coupled to saidquill shaft for actuating same, and mechanism for creating a travel ofthe head over the surface to be ground and means for drawing thecontaminated air from within said duct.

2. A grinding unit for cylindrical surfaces con-- prising, a shieldadapted to encompass said surfaces, means for adjustably attaching theshield to said surfaces, a quill casing of tubular form connected withthe shield and extending therefrom in a predetermined directionalmanner, a saddle mounted on the casing, a quill housing adjustablewithin the casing and spaced therefrom to provide an evacuating ducttherebetween, a quill shaft longitudinally disposed within said housingand having its operating head located adjacent the surfaces and adaptedto hold a grinding wheel for processing same, mechanism mounted on theCasing and coupled to said quill shaft for actuating same, mechanism forcreating a travel of the head over the surface to be ground, and meansfor supporting the unit and counterbalancing portions thereof, tocontrol the operable effect of the grinding wheel on said head.

3. A grinding unit for cylindrical surfaces comprising, a shield adaptedto encompass said surfaces, means for adjustably attaching the shield toaid surfaces, a quill casing of tubular form connected with the shieldand extending therefrom in a predetermined directional manner, a saddlemounted on the casing, a quill housing adjustable within the casing andspaced therefrom to provide an evacuating duct therebetween, a quillshaft longitudinally disposed within said housing and having itsoperating head located adjacent the surfaces and adapted to hold agrinding wheel for processing same, mechanism mounted on the casing andcoupled to said quill shaft for actuating same, mechanism for creating atravel of the head over the surface to be ground, means for supportingthe unit and counterbalancing portions thereof to control the operableeffect of the grinding wheel on said head, and means for actuating theunit and guiding it in conformity with the operable movement of saidsurface during its operation within the equipment.

4. A grinding unit for cylindrical surfaces comprising, a shield adaptedto encompass said surfaces, means for adjustably attaching the shield tosaid surfaces, a quill casing of tubular form connected with the shieldand extending there- 'rcm in a predetermined directional manner, asaddle mounted on the casing, a quill housing adjustable within thecasing and spaced therefrom to provide an evacuating duct therebetween,a quill shaft longitudinally disposed within said housing and having itsoperating head located adjacent the surfaces and adapted to hold a ndingwheel for processing same, mechanism unted on the casing and coupled tosaid quill .1 aft for actuating same, mechanism for creating 9 travel ofthe head over the surface to be ground, lalpanf} for supporting the unitand counterbalancing portions thereof to control the operable effect ofthe grinding wheel on said head, means o actuating the unit and guidingit in conformity h the operable movement of said surface duritsoperation within the equipment, and means said shield for permitting avisual inspection he interior thereof and the surfaces encomsse-cltherein being processed.

5. A grinding unit for use with crank shaft comprising, a shield adaptedto encompass said crank shaft surfaces, means for adjustably attachingthe shield to said surfaces, a quill casing of tubular form connectedwith the shield and extending therefrom in a predetermined directionalmanner, a saddle mounted on the casing,

. .iill housing adjustable within the casing and ced therefrom toprovide an evacuating duct 'ebetween, a quill shaft longitudinally disedwithin said housing and having its operathead located adjacent thesurfaces and adaptto hold a grinding wheel for processing same,mechanism mounted on the casing and coupled to said quill shaft foractuating same, mechanism for creating a travel of the head over thesurface to be ground, means for supporting the unit and counterbalancingportions thereof to control the operable effect of the grinding wheel onsaid head, mean for actuating the unit and guiding it in conformity withthe operable movement of said surface during its operation within theequipment, means in said shield for permitting a visual inspection ofthe interior thereof and the surfaces encompassed therein beingprocessed, and means for conducting the air from the evacuating duct toan extraneous locus.

WALTER F. EMORY.

REFERENCES CITED he following references are of record in the file ofthis patent:

UNITED STATES PATENTS

